In the technical field of communications, signal received power is usually used for power control and selection of a cell, a transmitting node or a receiving node. Power control is an effective solution for achieving uplink adaption and interference control. In an existing long term evolution (Long Term Evolution, LTE) R8-R10 system, uplink power control is based on open loop control and closed loop control, wherein the open loop control part is achieved based on path loss estimation, and the path loss estimation is obtained based on reference signal received power (Reference Signal Received Power, RSPR); and the closed loop control is performing closed loop correction to the open loop control part. The above-mentioned uplink power control solution may work quite well for conventional antenna configuration of a base station, wherein the conventional antenna configuration of the base station has a fixed downward tilt angle, and uplink and downlink experience similar path losses, thus downlink path loss may be nicely used for estimating uplink path loss. In addition, RSRP of a present cell/node or a neighboring cell/node reported by a user equipment (User Equipment, UE) may be used by a base station or an evolved node B (evolved Node, eNB) to select a serving cell or node for the UE.
To reduce system cost while achieving higher system capacity and coverage requirement, active antenna systems (Active Antenna Systems, AAS) have been widely deployed in practice, and at present, an upcoming LTE R12 standard is considering enhancement of communication performance by introducing an AAS system. Unlike a conventional base station antenna, the AAS further provides a design freedom in a vertical direction of an antenna. In this case, uplink and downlink may adopt independent downward tilt angles, both of which may be controlled flexibly. Under this circumstance, in an existing LTE R8-R10 system, a method for achieving power control or selecting a cell/node based on downlink reference signal received power in the prior art is not effective any more.